The invention pertains to coupling mechanisms for adjoining a length of flexible hose to another length of hose, a rigid pipe fitting, a T-intersection or anything else, and particularly relates to such a coupling or fitting as it would apply to irrigation systems.
There are numerous different types of irrigation systems, to some of which the instant invention may not apply. The area to which it particularly does apply is a specialized field of irrigation in which very lightweight, thin-walled flexible plastic tubes are temporarily, or at most semi-permanently deployed in sugar cane groves or elsewhere such that they must be dismantled and discarded after a period of time. The assembly of these units must naturally be accomplished in as rapid a time as possible because of the economics of farm labor and this in turn requires the utilization of fittings and couplings which are capable of connecting the length of thin-walled hose to pipes and the like absolutely as quickly as possible.
There has been utilized in the past a coupling which utilized an elongated tubular body portion somewhat like the one of the instant invention with a nipple onto which the end of a hose is pushed and then quickly retained thereon by virtue of a collar threadedly engaged on the coupling body which moved out to pinch a hose over the nipple as the collar is rotated on its threads, causing it to axially advance on the coupling tube.
This unit has functioned quite adequately for several years and has been sold in great quantity, but has left room for improvement in the following two areas.
First, during the coupling operation when the collar is rotated on its retaining threads, there is a tendency for the collar to cock back or skip over the threads rather than advance forward against the force of the hose as it is compressed around the nipple. Second, the only movement capable of engaging or disengaging the irrigation hose in the prior art coupling was the rotative adjustment of the collar; in other words, the collar could not be directly moved axially either onto or off of the irrigation hose but had to be rotated to effect axial motion because it was captured on the threads of the coupling body.